In certain applications such as in the aircraft and vehicular industries it can be desirable to reduce the overall weight of materials. For example, the weight of a polymeric composition such as an aerospace coating or sealant can be reduced by incorporating low density fillers. In aerospace applications, coatings and sealants must meet a number of demanding performance requirements including adhesion, tensile strength, elongation, and high temperature stability, and these properties must be maintained following exposure to aviation fuel and other aviation fluids. Low density fillers such as hollow polymeric microspheres can be effective in reducing the overall density of a polymeric composition but also tend to swell upon exposure to aviation fuel causing degradation in the physical properties of a cured coating or sealant. Inorganic fillers provide reinforcing effects that result in improved tensile strength and percent elongation but can also increase the density of the cured coating or sealant.